Discussion part of the paper itself is much better read than the article.<p><a href="http://journals.sagepub.com/doi/full/10.1177/0031512516640391" rel="nofollow">http://journals.sagepub.com/doi/full/10.1177/003151251664039...</a><p>>It would be informative to conduct a similar experiment with a population of experienced barefoot runners to determine whether they would also experience WM improvements. It is possible that the increased attentional focus may be automated after an extended period of running barefoot. Conversely, barefoot running may be sufficiently challenging that increased attention is always required and thus would even experienced barefoot runners would see an improvement in WM.<p>This is very good question and the subject itself is interesting.<p>There is certain type of 'elevated feeling' you get after some intense activity that requires certain amount of conscious and unconscious proprioception. It feels like you have been 'activated'.<p>The activity may be period of intense FPS-gaming, running barefoot (especially first times), or lifting free weights instead of using weight machines, doing yoga, juggling or martial arts and learning more difficult moves.<p>The question is if the activity is challenging enough that it can't be completely controlled by unconscious proprioception or is the increase in difficulty level necessary to get same result.